Sewing machine



Nov. 2 1926.

H. E. C. WALPOLE SEWING MACHINE Filed Oct. 26, 1925 4 Sheets-Sheet 1Nov. 2 1926.

H. E. C. WALPOLE SEWING MACHINE Filed Oct, 26, 1925 4 Sheets-Sheet 2Nov. 2 1926." 1,605,308

H. E. C. WALPOLE SEWING MACHINE Filed Oct. 26, 1925 4 Sheets-Shoot 3Nov. 2 1926.

H. E. c. WALPOLE SEWING MACHINE 4 Sheets-Sheet 4 Filed Oct. 26, 1925Patented Nov. 2, 1926.

HORACE EDWARD CHRISTOPHER WALPOLE, OF EIPSOM, ENGLAND.

SEWING MACHINE.

Application filed October 26, 1925, Serial No.

This invention relates to sewing machines such as are used in themanufacture of boots and shoes, and it relates particularly to that typeof machine known in the trade as the Blake machine.

In this invention simple and efficient mechanism is provided for sewingthe soles to boots and shoes or the like. At the same time provision ismade for controlling the rise and fall movement of thepresser bar insuch a manner that it has a uniform lift.

The machine is provided with a main frame of suitable shape and carryinga pair of bearings in which is mounted the driving shaft. 011 one end ofthis shaft is mounted a disc having formed on one side a number oftappets which give motion to a lever working horizontally and pivotallymounted on one side of the frame. On the other side of the said disc isformed an eccentric on which works an eccentric strap connected to oneend of a double ended needle lever, the other end of the said leverbeing connected by means of a link to a vertical reciprocating 25 needlebar, whereby motion is given to a pointed hook carried by the last namedbar.

The said horizontal lever, which is actuated by the tappets formed orfixed on the disc, is arranged to operate a vertically oscillatinglever,pivoted at or about its centre, for giving a backward and forwardmotion which in turn is transmitted through a connecting link to aholder in which is fixed a feed point. The feed holder is arranged towork in a slotted plate which is attached to the presser bar and whichgives the feed point holder a downward movement for piercing the work.

On the pin or spindle by which the feed to point holder is connected tothe said link is mounted a tappet lever which is arranged to engage witha pin in the presser bar, and which causes the work to be fed forward toa distance corresponding with the length of the stitch to be sewn.

To the presser bar is fixed the presser foot which holds down the workfor the period during which the needle is in operation, and the presserbar is afterwards lifted by a 0 pivoted lever, one end of the saidpivoted lever being in engagement withan eccentric or cam mounted on thedriving shaft, and

v the other end of the lever is in engagement with an eccentric block orsnail cam, a por- 64,957, and in Great Britain October 9, 1924.

tion of the periphery of which is serrated. By the presser bar beingthus lifted the feed point is enabled to pierce and feed the workforward.

By employing the just namedcircularly racked snail cam which engageswith the said pivoted lever a uniform amount of lift is given to the'presser bar, no matter what the varying thicknesses of the materialbeing operated upon. The snail cam rests on the end of the said pivotedlever and by the latter being actuated by a cam or eccentric on the mainshaft the necessary rise and fall is given to the presser bar at thetime required. v

A pawl is arranged to engage the racked portion of the snail cam and thepawl is controlled,through a bell crank lever and compensatingarrangement,-by a connecting link attached to one end of the hori-Zontally working lever above described, and as this lever has areciprocating motion a rise and fall motion is imparted to the said pawlwhich looks and unlocks the snail cam at the required time.

A second pawl is employed in addition to that just described for lockingthe ,presser bar as the needle is being withdrawn. This second pawl iscontrolled by a pivoted lever actuated by a cam or eccentric on thedriving shaft, and it is arranged to work directly on to a rackedportion of the presser bar.

A. suitably shaped horn fitted and housed in the main framework of themachine is provided, and upon which the work is placed. The said horn isfitted with suitable gears and shafts all of which receive their motionfrom a main gear fixed on the driving shaft of the machine. The machineis provided with an automatically regulated thread drawing arrangementwhereby the correct amount of thread is drawn-for the sewing operation.

In the drawings hereunto annexed- Fig. 1 is a side elevation of thesewing machine according to this invention;

Fig. 2 an end elevation of the same looking from the right of Fig. 1;

Fig. 3 an elevation showing the opposite side of the machine to thatillustrated in Fig. 1;

Fig. 4 a plan of Fig. 3; Fig. 5 an enlarged end elevation of the feedpoint holder and a portion of the mech anism for traversing its forwardand causing it to pierce the work being operated upon;

Fig. 6 a plan of the mechanism shown in Fig.

Fig. 7 a side elevation of an arrangement for putting friction on to theneedle bar;

Fig. 8 a plan of the same.

Like parts in all the views are marked with similar reference numerals.

1 is the upper portion of the framework of the machine'to which issecured the bearing 2 in which is mounted the spindle 3 of the horn 4t.5 is the driving shaft carried in the bearings 6, 6 fixed to theframework 1. The front of the upper portion of the framework 1 isbifurcated at 7, 7 in which are formed bearings for the needle bar 8 andpresser bar 9.

On the driving shaft- 5 is mounted an eccentric 10 provided with thestrap 11 having a projection 12 integral therewith. The upper end of theprojection is attached to the end of the beam 13 which is fulcrumed at15 to the adjustable fulcrum post 16 cartied in bearings 17 and 18 whichform part of the framework 1, the opposite end 19 of the beam '13 isattached by a link 20 to the needle bar 8. In the lower end of theneedle bar 8 is secured a hooked needle 21.

rotary motion is imparted tothe driving" shaft 5 from any suitablesource of power, and motion is communicated to the whirl 22, whichrotates in bearings 23 formed for its reception in the upper'end of thehorn any means of a bevel wheel gearing with a'bcvel pinion 25 mountedon the end of the'inclined shaft 26 to a pair of m'itre wheels 27 and 28mounted respectiye'ly-on the end of the shafts 26'and 29, and'th ence'tothe'bevel wheels 30 and 31 mounted respectively on one end of shaft 29'and to a vertical shaft 82 of the bevel wheel 33 fixed on the upper endof the ver ticalsha ft 32 and from thence to bevel pin ion fixed on theshaft 35" to the mitre wheels 86, 37 formedrespectively on the bosses38., 39 fixed upon the ends of shafts and 40, to hevelteeth 41 formed inthe end of shaft 49, which teeth gear with the teethfitil of the whirl22. The'whirl is proviaeawah the usual h0le,- -not shown in thedrawirigsf through which the thread passes.

All the above described parts, with the exceptibn oftlie eccentric10,are of the usual and ordinary'construction, such as are found oneBlake sewing inachine,"and will be readily understood without furtherdescription. i On the driving shaft 5 is mounted and fixed'a' disc 43t'o on'e'end of which is fixed or formed the eccentric 10 which operatesthe beam 13. the other side of the disc 43 is "or'are formed or fixedone or more suitably shaped tappets -14 (Figs. 2 and l) for impartingthe requisite motion to a double ended horizontal lever 45 which ismounted upon a vertical fulcrum carried by the lug 47 formed on theframework '1. 1n the horizontal lever 15 provision is made for mountinga'bowl orrunner (58 on a pin (59. The bowl G9 is arranged to engage withprojections or tappets H on the disc 45'). The horizontal lever 45 isconnected to a vertical reciprocating lever d8 which is fulcruined upona headed pin 49 carried by a lug 59 formed on the framework 1. 1n theupper end 51 of the vertical lever 41-8 is fixed a pin 52 which works ina slot 53 formed for its reception in the enlarged front end 54 of lever45. The position of the end 5 t of the lever 4:5 in regard to the pin 52may be adjusted by means of the set screw To the lower end of lever 4-8is attached one endof a link 56 which is bifurcated at both its ends; Inthe opposite end of link 56 is loosely mounted a pin 57 which projects asuitable distance on one side of the link so as to permit of it workingin a slot 58 formed in a plate 59 which is fixed to th p'resser bar, 9.

' On the end of the pin 57 is fixed the feed point holder 60, the plate59 being arranged between one of the sides of the said holder and of onearm of the bifurcated end of link In the holder 60 is mounted a feedpointGl i 'hich is secured in position by set screw 62.

Between the arms of the bifurcation of link 56 is mounted a hooked leverwhich is secured by a pin 64 passing transversely through the pin 57.The hooked end of lever, 63 is arranged to engage with a pin (35 fixedto the presser'bar, as shown at Fig. 6.- The lower end of the presserbar 9 is niio dified so as 'to adaptit for working in qnj 'aetign withthe feed point 61 and its holder 60 and it is provided with an adjustable projecting portion 66 shaped at its lower end to pass into thechannel formed in thesole of the boot to be sewn. The projection 66 isretained in position by a set screw 67.

To impart a uniform amount of lift to the presser bar 9 irrespvtive ofthe thickness of thesole or substance to be sewn, the circular block ismounted eccentrically on the presser bar; 9,o r the said blockinay be inthe form of asna'il cam 'ZO' which is provided at a portion of its'periineter 'with ratchet teeth 71. Thesaid block will hereinafter bereferred to tlie'snail cam '70, and it is mounted'loo'selyupona pin 72.one end of whiclris screwed into the presser bar 9 so that the pinprojects at a right angle thereto. The snail cam 70 is provided with aboss 73 having a groove formed in its periphery for the reception of aspiral spring 7 1 which is attached at one end 75 to the Ill snail cam70, and the spring after passing over the boss 73 is secured atitsropposite end by a set screw 76 to one end of a second double endedlever 77.

The lever 77 is pivoted at 78 to the frame work 1 and it is arranged,when operated, for its front end to reciprocate in a vertical direction.The perimeter of the snail cam is arranged to rest upon the uppersurface of the front end of lever 77.

The rear end of lever 77 is arranged to be operated by a cam 79 mountedupon the driving shaft 5 whereby an intermittent up and down motion isimparted to the front end of the lever 77 and to the presser bar 9.

Above the snail cam 70 and mounted upon a headedset screw 80 is a pawl81 provided with a heel 82.

To the said heel 82 and pawl 81 is attached a compensating arrangementcomprising aspiral spring 83 into which is passed the end of a rod 84;.The spring at its lowest end is hooked on to the heel 82 and the upperportion of rod 84: is anchored at 85 by means of a hook to one arm of abell crank lever 86 (Fig. 2) which is mounted on a pin 87 fixed to theupper end of the presser bar 9. The second arm of the bell crank leveris connected by a link 88 to a projection 89 formed on the enlarged end54: of lever 45.

()n thedriving shaft 5 is also fixed a second cam 90 which actuates witha lever 91 pivoted at 92 to the framework 1. The front end of lever 91is connected by a compensating arrangement consisting of a spring 98 anda rod 9 1 to alever 95 fixed onone end of ahori'zontal spindle 96carried in a bracket 97. On the end of the spindle 96 is fixed a secondpawl 98 which is arranged to engage with the teeth 99 formed on one ofthe sides of the presser bar 9.

The requisite friction is placed upon the needle bar 8 by means of ablock 100 (Figs. 7 and 8) which is placed in a recess 101 formed for itsreception in one arm of the bifurcation 7 of the framework. Thisfriction creates a pause on the needle bar when the latter is at the topand bottom of its stroke thus permitting the whirl 22 to loop the threadaround the needle or hook. Obviously, if only an up and down motion wereimparted to the needle bar, the whirl could not rotate quick enough toform the loop for the needle, and consequently the friction on the baris an important factor in the efficient operation of the machine.Moreover, as the fulcrum post 16 is longer than the depth of the frameit slides in, it will assist in imparting the desired pause to theneedle bar.

The requisite pressure is imparted to the block by means of a pin 102,the outer end of which is arranged to abut against the [lat spring 103,shaped as shown at Fig.

to lift the 8, and the tension of the said spring is capable ofadjustment by means of the set screws 10 1.

The block 100 is provided with the lips 105 which prevent it fromfalling out of position.

106 is a lever which is employed for drawing the thread from the reel orcop. The said lever is fulcrumed at 107 to the framework 1 of themachine, and it is shaped as shown at Fig. 3, the front end of the leverbeing arranged to rest upon a pin 108 fixed to the presser bar 9. Thelength of the thread drawn from the bobbin or spool or cop may beadjusted by means of a projection 109 formed on the boss 110 fixed. tothe fulcrum posts 16 by means of a set screw 111.

In the pin 108 is mounted an adjusting Screw 112 for regulating thedownward movement of the presser bar 9.

The action of the machine is as follows On motion being imparted to thedriving shaft 5 in the usual manner, the beam 13 is caused,by theeccentric 10 and its strap 11.to oscillate, whereby the needle bar 8 isvertically reciprocated. The presser bar 9 is also brought intooperation by the cam 79 and pivoted lever 77, and it is so timed thatthe work being operated upon is held in position during the sewingoperation and the withdrawing of the hooked needle 21 from the work.

If. owing to the varying thicknesses of the material being operatedupon. the presser bar 9 is slightly lifted. this lift is compensated forby the snail cam 70 being partially rotated by the spring 7 1 so that aportion of the periphery of the said cam 70 comes into contact with thefront end of the lever77 whereby the presser bar 9 is lifted a uniformdistance. no matter what the varying thicknesses of the material may be.

Prior to the lifting of the presser bar 9, and during the time that theneedle bar 8 is down, the pawl 81 is brought into engagement with theracked periphery 71 of the snail cam 70 by the movement of thehorizontal lever 45 and the said snail cam is thus locked in thisposition. The cam 79 on the driving shaft 5 causes the lever 77 presserbar 9 about one-eighth of an inch. Immediately this lift has taken placethe pawl 98 is caused to engage the teeth 99 cut in the presser bar 9.This is accomplished by the cam 90 mounted upon the driving shaft 5 andwhich oscillates the lever 91 which is connected to the lever 95 on thespindle 96. In this manner the presser bar 9 is prevented from liftingwhen the needle comes out of the work.

When the needle bar 8 is at or about its highest point and the presserbar 9 has been slightly raised, the tappet 44 on the bOWl or runner 68carried by the horizontal lever 15, whereby the enlarged end 54 of thesaid lever is caused to move inwards and by its connection with thevertically reciprocating lever 48 the link 56 is caused to be drawn inthe direction of arrow A. Simultaneously with this movement the pin 57is moved down the slot 58 in the plate 59 and the holder 60 is depressedfor causing the feed point 61 to enter the leather. At the same time theinner surface of the hooked lever 63 engages with the pin 65 and theholder 60 is caused to move in the direction of arrow B and feed theWork forward. On further rotation of the disc 453 the horizontal lever land parts connected therewith are returned to their normal position bythe spring 113. This operation may be repeated de novo.

The projection 109 fixed on the fulcrum post 16 is arranged to engagethe lever 106, and by its front end resting on the pin 108 fixed onthepresser bar 9, the needle bar is caused to rise and fall according tothe position in which the lever 106 isadjusted, and thereby drawing moreor less thread according to the length of stitch it is desired to form.

The stitch is formed by the Wllll'l 22 and the other parts of themachine operate in the usual and ordinary manner.

What I claim is 1. A sewing machine having in combination a drive shaft,a presser bar, a feed point member connected to said presser bar, ahorizontal lever connected to said feed point member, a disc secured tosaid drive shaft and having tappets thereon adapted to engage a portionof said lever whereby the Wort is advanced through the machine, asnail-cam on said presser bar, and means operatively connecting said camto said drive shaft for imparting a uniform lift to the presser bar.

2. A sewing machin having in combination, a drive shaft, a needle bar, aprcsser bar, a feed point member, a horizontal lever connected. to saiddrive shaft ant. said feed point member, a snail cam on said presscrbar, means connecting said cam to said drive shaft, a locking deviceassociated with said cam and operated by said horizontal lever, andmeans operable by said drive shaft for locking the presser bar in apredetermined position during the operation of the machine.

A sewing machine having in combination a drive shaft, a presser bar, afeed point member connected to said presser bar, a horizontal leverconnected to said feed point member, a disc secured to said drive shaftand having tappets thereon adapted to engage a portion of said lever forimparting a lateral n'iovement thereto, a snailcam on said presser bar,means operatively connecting said cam to said drive shaft for liftingthe presser bar, means operated by the movement of said horizontal leverfor locking the snail-cam in position, and lockingmeans associated withthe presser bar and connected with the drive shaftfor positivelypreventing the presser bar from moving when the needle comes out of theWork.

HORACE EDWARD CHRISTOPHER WALPOLE

